It looks like I've run into the problem described at http://code.google.com/p/arduino/issues/detail?id=380 where I can't upload sketches larger than 28,992 bytes.

A solution at http://forums.adafruit.com/viewtopic.php?f=31&t=19243#p100082 describes a way to patch my existing Uno rev 1 using a second Arduino. I don't have one or know anyone who has one that I could borrow though.

Is there any way to do this without a second Arduino ?

Failing that, can this fix be done from a Mega? If I have to buy a new one to fix this problem, I figure I may as well get something with more memory.

It looks like I've run into the problem described at http://code.google.com/p/arduino/issues/detail?id=380 where I can't upload sketches larger than 28,992 bytes.

A solution at http://forums.adafruit.com/viewtopic.php?f=31&t=19243#p100082 describes a way to patch my existing Uno rev 1 using a second Arduino. I don't have one or know anyone who has one that I could borrow though.

Is there any way to do this without a second Arduino ?

Buy a 328P chip with a bootloader preburned into it?

Failing that, can this fix be done from a Mega? If I have to buy a new one to fix this problem, I figure I may as well get something with more memory.

Yes, arduinoISP is just a sketch and can therefore be run on a mega board.